Discussion

Explanation:

Let the first term of the GP be ‘a’ and the common ratio is ‘r’.

Given, T₁₀ = 4 × T₈

⇒ ar⁹ = 4 × ar⁷

⇒ r = ±2

Now, S₁₀ = 2046

⇒ $\frac{a(r^{10}-1)}{r-1}$ = 2046

Case 1: r = +2
⇒ $\frac{a(1024-1)}{2-1}$= 2046
⇒ a = 2

Case 2: r = -2
⇒ $\frac{a(1024-1)}{-2-1}$ = 2046
⇒ a = -6

∴ a = -6 or 2

Hence, option (c).

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